Catalytic emulsion polymerization of norbornene

The use of late transition metal catalysts for the polymerization of olefins in aqueous media has created new opportunities to produce latex particles based on ethylene and its olefinic derivatives. This thesis reports on three different aspects of the catalytic emulsion polymerization of norbornene; (1) reaction parameters (e.g. reaction temperature, ionic strength), (2) addition of various classes of surfactants, and (3) polymerization of a variety of norbornene-derived monomers. These reactions have been carried out as ab initio batch emulsion polymerizations using allyl palladium catalysts and a lithium based activator, supported by a variety of surfactants. The role of surfactants in traditional emulsion polymerization is to assist in particle nucleation and/or to stabilize latex particles. We studied the role of several classes of surfactants in the emulsion polymerization of norbornene with Pd catalysts, both with and without the activator LiFABA. In the catalytic emulsion polymerization of norbornene, some of these surfactants were found to act as weakly coordinating anions with the Pd based catalysts to promote polymerization. When the base latex recipe already contains an activator specifically designed to work effectively with Pd in organic media (e.g.LiFABA), certain classes of surfactants (e.g. sulfates) act to provide an alternative pathway for polymerization and latex particle formation. Other surfactants (e.g. cationics) can actually suppress all or part of the polymerization by destructively interfering with either the catalyst or the activator. Alkyl sulfates and sulfonates were both effective activators of allyl Pd catalysts and produced latex particles (ca. 40--50 nm) without significant amounts of coagulum. This activity is significantly dependent on the alkyl chain length, and alkyl sulfate anions are more active than the equivalent alkyl sulfonate anions. Cationic, fatty acid and non-ionic surfactants produced variable, but ineffective, results in our studies. This work determined that the n-alkyl norbornenes can be polymerized in aqueous emulsion and that the mechanisms for latex particle formation are the same as that for norbornene monomer alone. As in the case of norbornene, large amounts of coagulum can be formed if the catalyst and activator are allowed to reach the emulsified monomer droplets and effect polymerization in that location. As the substituents on the norbornene become larger and non-polar, it is necessary to consider their effect on the water solubility of the monomers in order to analyze the experimental results in an effective manner. Our studies included butyl and decyl-norbornene, vinyl and butenyl-norbornene, and methanol-norbornene in ab initio emulsion polymerization and also the mini-emulsion polymerization of decyl-norbornene

High-Speed Real-Time Simulators for Engineering Design

The use of computer simulations is now an established technique in engineering design. Many of these simulations are used to predict the expected behavior of systems that are not yet built, or of existing systems in modes of operation, such as catastrophic failure, in which it is not feasible to test the real system. Another use of computer simulations is for training and testing purposes in which the simulation is interfaced to real hardware, software and/or a human operator and is required to operate in real-time. Examples are plant simulators for operator training or simulated environments for testing hardware or software components. The primary requirement of a real-time simulation is that it must complete all the calculations necessary to update the simulator outputs as well as all the necessary data I/O within the allotted frame time. Many real-time simulations use frame times in the range of a few milliseconds and greater.There is an increasing number of applications, for example in power electronics and automotive systems, in which much shorter frame rates are required. This paper reviews some of these applications and the approaches to real-time simulation that can achieve frame times in the range 5 to 100 microseconds.

Cost-effectiveness of the Manchester approach to identifying Lynch syndrome in women with endometrial cancer

This is the final version. Available on open access from MDPI via the DOI in this recordLynch syndrome (LS) is a hereditary cancer syndrome responsible for 3% of all endometrial cancer and 5% in those aged under 70 years. It is unclear whether universal testing for LS in endometrial cancer patients would be cost-effective. The Manchester approach to identifying LS in endometrial cancer patients uses immunohistochemistry (IHC) to detect mismatch repair (MMR) deficiency, incorporates testing for MLH1 promoter hypermethylation, and genetic testing for pathogenic MMR variants. We aimed to assess the cost-effectiveness of the Manchester approach based on primary research data from clinical practice in Manchester. The PETALS study informed estimates of diagnostic performances for a number of different strategies. A recent microcosting study was adapted and used to estimate diagnostic costs. A Markov model was used to predict long-term costs and health outcomes (measured in quality-adjusted life years, QALYs) for individuals and their relatives. Bootstrapping and probabilistic sensitivity analysis were used to estimate the uncertainty in cost-effectiveness. The Manchester approach dominated other reflex testing strategies when considering diagnostic costs and Lynch syndrome cases identified. When considering long-term costs and QALYs the Manchester approach was the optimal strategy, costing £5459 per QALY gained (compared to thresholds of £20,000 to £30,000 per QALY commonly used in the NHS). Cost-effectiveness is not an argument for restricting testing to younger patients or those with a strong family history. Universal testing for Lynch syndrome in endometrial cancer patients is expected to be cost-effective in the UK NHS, and the Manchester approach is expected to be the optimal testing strategy.Medical Research Council (MRC)National Institute for Health Research (NIHR

HE4 as a Biomarker for Endometrial Cancer

There are currently no blood biomarkers in routine clinical use in endometrial carcinoma (EC). Human epididymis protein 4 (HE4) is a glycoprotein that is overexpressed in the serum of patients with EC, making it a good candidate for use as a diagnostic and/or prognostic biomarker. HE4 is correlated with poor prognostic factors, including stage, myometrial invasion and lymph node metastases, which means it could be used to guide decisions regarding the extent of surgery and need for adjuvant therapy. Serum HE4 has also shown promise for predicting responses to progestin therapy in early-stage EC. The use of algorithms and indices incorporating serum HE4 and other biomarkers, including clinical and imaging variables, is an area of increasing interest. Serum HE4 levels rise with age and renal dysfunction, which may affect the interpretation of results. This review covers the evidence supporting the use of HE4 as an EC biomarker for diagnosis, prognosis, recurrence monitoring, and prediction of therapy response. The evidence for combining serum HE4 with other biomarkers, including clinical and imaging variables, its value as a biomarker in other biofluids and potential challenges of its clinical use are also discussed

Serum CA125 and HE4 as Biomarkers for the Detection of Endometrial Cancer and Associated High-Risk Features

Early detection of endometrial cancer improves survival. Non-invasive diagnostic biomarkers would improve triage of symptomatic women for investigations. This study aimed to determine the diagnostic accuracy of serum Cancer Antigen 125 (CA125) and Human Epididymis 4 (HE4) for endometrial cancer and associated high-risk features. Serum samples from women investigated for gynaecological symptoms or diagnosed with endometrial cancer were analysed for CA125 and HE4. Conventional diagnostic metrics were calculated. In total, 755 women were included; 397 had endometrial cancer. Serum CA125 and HE4 were significantly elevated in cases compared with controls (both p < 0.001), and with pathological markers of disease severity (p < 0.05). A combination of CA125 and HE4 detected endometrial cancer with an area under the curve (AUC) of 0.77 (95% CI: 0.74–0.81). In a model with body mass index (BMI) and parity, HE4 predicted endometrial cancer in pre-menopausal women with an AUC of 0.91 [sensitivity = 84.5%, specificity = 80.9% (p < 0.001)]. In women with abnormal ultrasound, HE4 ≥ 77 pmol/L improved specificity compared with imaging alone [68.6% (95% CI: 75.0–83.6) vs. 34.4% (95% CI: 27.1–42.3), respectively], but at a cost to sensitivity. HE4 ≥ 77 pmol/L improved the detection of myometrial invasion ≥50% in women with stage I disease compared with magnetic resonance imaging (MRI) alone [sensitivity = 100% (95% CI: 54.1–100)]. CA125 ≥ 35 U/mL did not add to imaging. HE4 is a good predictor of poor prognostic features which could assist staging investigations

Observational evidence for the convective transport of dust over the central United States

Bulk aerosol composition and aerosol size distributions measured aboard the DC-8 aircraft during the Deep Convective Clouds and Chemistry Experiment mission in May/June 2012 were used to investigate the transport of mineral dust through nine storms encountered over Colorado and Oklahoma. Measurements made at low altitudes (\u3c5 km mean sea level (MSL)) in the storm inflow region were compared to those made in cirrus anvils (altitude \u3e 9 km MSL). Storm mean outflow Ca2+ mass concentrations and total coarse (1 µm \u3c diameter \u3c 5 µm) aerosol volume (Vc) were comparable to mean inflow values as demonstrated by average outflow/inflow ratios greater than 0.5. A positive relationship between Ca2+, Vc, ice water content, and large (diameter \u3e 50 µm) ice particle number concentrations was not evident; thus, the influence of ice shatter on these measurements was assumed small. Mean inflow aerosol number concentrations calculated over a diameter range (0.5 µm \u3c diameter \u3c 5.0 µm) relevant for proxy ice nuclei (NPIN) were ~15–300 times higher than ice particle concentrations for all storms. Ratios of predicted interstitial NPIN (calculated as the difference between inflow NPIN and ice particle concentrations) and inflow NPIN were consistent with those calculated for Ca2+ and Vc and indicated that on average less than 10% of the ingested NPIN were activated as ice nuclei during anvil formation. Deep convection may therefore represent an efficient transport mechanism for dust to the upper troposphere where these particles can function as ice nuclei cirrus forming in situ

Application of a Predictive Coke Temperature Model to Heat Stress Experimentation

An interactive procedure for evaluating and maintaining an individual's core temperature at a predetermined level was developed and tested. The procedure involved the use of previously developed models for predicting core temperature changes during work and rest. Various levels of metabolic activity were used for rapid core temperature elevation and adjustments in dry-bulb temperature and relative humidity maintained the desired core temperature level. Evaluation of the procedure was made using five female subjects at four different levels of elevation. Results are presented which show the accuracy of the control.Yeshttps://us.sagepub.com/en-us/nam/manuscript-submission-guideline

A 1- to 5-MW, RCS-based, short-pulse spallation neutron source

Two accelerator configurations, the linac/compressor ring scheme and the linac/RCS scheme, are commonly used to provide the proton beam power for a short-pulse spallation neutron source. In one configuration, a full-power linac provides the beam power and a compressor ring shortens the pulse length from 1-ms down to 1 {micro}s. In the other, rapid cycling synchrotrons (RCSs) provide the beam power and also shorten the pulse length. A feasibility study of a staged approach to a 5-MW proton source utilizing RCS technology, allowing intermediate operation at 1 MW, was performed at ANL and is presented in this paper. This study is complementary to a study in progress at ORNL based on a linac and an accumulator ring. The 1-MW facility consists of a 400-MeV injector linac that delivers 0.5-mA time-averaged current, a synchrotron that accelerates the beam to 2 GeV at a 30-Hz rate, and two neutron-generating target stations. In the second phase, the 2-GeV beam is accelerated to 10 GeV by a larger RCS, increasing the facility beam power to 5 MW